Feedback apparatus and method for improving x-factor

ABSTRACT

An X-factor feedback apparatus senses three-dimensional direction information of the shoulder and the pelvis in a golf swing motion of a user, collects, synchronizes and stores the sensed three-dimensional direction information, analyzes the change of angle in the three-dimensional direction information based on the stored data information, extracts a backswing top point in the swing motion, evaluates the degree of twist of the shoulder and the pelvis based on the angle in the three-dimensional direction information of the shoulder and the pelvis at the backswing top point, and provides a feedback to the user.

BACKGROUND

1. Field

The present disclosure relates to analyzing and correcting twist of anupper body when a user performs a golf swing, and more particularly, toa method and apparatus for providing a graded feedback by collecting andanalyzing data about an X-factor according to the progress of swing byinputting a golf swing motion of the user.

2. Description of the Related Art

Even though the golf has become popular and related industries have beendeveloped, the golf is one of sports whose skills are not easilytrained. This is because the golf swing requires a complicated mechanismcomposed of fixation of the line of vision, center of gravity, movement,swing trajectory or the like, rather than physical conditions. Toovercome this, there is demanded a device capable of providing asuitable feedback to a user by using automatic analysis and numericaland visual information about essential factors of a correct swing inorder to induce the improvement of swing.

As described above, in such an automatic analyzing device for essentialelements of a golf swing, the importance of an X-factor, which is a keyelement for the improvement of an accurate impact and a fast club headspeed obtained by a stable swing posture, is increasing. The X-factorrepresents the change of a relative distortion (twist) or an anglebetween the upper body (or the shoulder) and the pelvis in a golf swing(an address, a backswing, a backswing top, a downswing, an impact, and afollow-through). In addition, the X-factor increases from the address tothe backswing top, and at the backswing top, the X-factor should have aconstant size to prevent an inaccurate impact from generating due toexcessive motion of the upper/lower body at the downswing. Moreover, bygenerating a strong impact by a stable twist of the upper and lowerbodies, a flying distance of a ball may increase. As described above,desirable twist of the upper body and the pelvis has a very closerelation with accurate impact, prevention of a slice, prevention of atopping hit, and the increase of a flying distance caused by theimprovement of a club head speed, and is so very important for theimprovement of a swing posture.

In order to improve the X-factor, in the conventional art, a user uses agolf swing exercise instrument to limit or facilitate the movement ofjoints such as the wrist, the shoulder and the pelvis of the user inorder to induce a mechanical swing exercise, or performs a musclereinforcing exercise for making strong muscles and impacts in order toimprove a flying distance.

Nevertheless, conventional golf exercise instruments do not provide asolution for a user to improve an X-factor since they are not able toanalyze and diagnose the X-factor and thus not able to provide asuitable feedback.

SUMMARY

The present disclosure is directed to providing a method for helping auser to recognize the degree of his X-factor in his swing motion andrepair problems of the swing motion by himself, without being limited toa simple muscle strengthening exercise, even though the user does notuse a separate instrument or specially-manufactured club which limits orfacilitates movement of the user.

In one aspect, there is provided an X-factor feedback apparatus, whichincludes: a sensing unit for sensing three-dimensional directioninformation of the shoulder, the pelvis and a golf club in a golf swingmotion of a user; an analyzing unit for calculating the change of anangle in the three-dimensional direction information of the shoulder andthe pelvis and extracting a backswing top point from the swing motion; adetermining unit for determining an angle in the three-dimensionaldirection information of the shoulder and the pelvis at the backswingtop point; and an output unit for providing feedback information to auser based on the determined angle.

In another aspect, there is provided an X-factor feedback method, whichincludes: sensing three-dimensional direction information of theshoulder, the pelvis and a golf club in a golf swing motion of a user;calculating the change of an angle in the three-dimensional directioninformation of the shoulder and the pelvis; extracting a backswing toppoint in the swing motion; determining an angle in the three-dimensionaldirection information of the shoulder and the pelvis at the backswingtop point; and providing feedback information to the user based on thedetermined angle.

According to an aspect of the present disclosure, it is possible toanalyze and evaluate an angle between the shoulder and the pelvis at abackswing top in the golf swing of a user and provide a feedback forimproving an X-factor to the user.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the disclosedexemplary embodiments will be more apparent from the following detaileddescription taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a simplified block diagram showing an apparatus for outputtingan X-factor evaluation according to an embodiment of the presentdisclosure;

FIG. 2 is a diagram showing an X-factor feedback apparatus according toan embodiment of the present disclosure;

FIG. 3 a is a diagram showing an analyzing unit of the X-factor feedbackapparatus according to an embodiment of the present disclosure;

FIG. 3 b is a diagram showing a backswing top motion point in theturning of a golf club according to an embodiment of the presentdisclosure;

FIG. 4 is a table showing an example of a feedback comment and a scoreaccording to an angle between the shoulder and the pelvis according toan embodiment of the present disclosure;

FIG. 5 is a flowchart for illustrating an X-factor feedback methodaccording to an embodiment of the present disclosure; and

FIG. 6 is a diagram showing the angle between the shoulder and thepelvis according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be described indetail with reference to the accompanying drawings.

FIG. 1 shows an apparatus 100 for receiving a golf swing motion of auser and outputting a graded feedback for the degree of twist of theshoulder and the pelvis (X-factor) of the user according to anembodiment of the present disclosure.

The X-factor feedback apparatus 100 according to an embodiment of thepresent disclosure senses the degree of twist (angle) between theshoulder and the pelvis based on the angle (three-dimensional directioninformation) between the shoulder and the pelvis in a sequential golfswing motion of the user, evaluates the degree of twist at a backswingtop point, and provides a graded feedback to improve the X-factor of agolf swing of the user.

Referring to FIG. 2, the X-factor feedback apparatus 100 according to anembodiment of the present disclosure includes a sensing unit 202 forsensing sequential three-dimensional direction information of theshoulder, the pelvis and a golf club of the user in a golf swing, a datastoring unit 204 for collecting, synchronizing and storing the sensedthree-dimensional direction information, an analyzing unit 206 forcalculating the change of angle (the degree of twist) in thethree-dimensional direction information of the shoulder and the pelvisbased on the stored data information and extracting a backswing toppoint in the swing motion, a determining unit 208 for determining anangle in the three-dimensional direction information (vector) at thebackswing top point, and an output unit 210 for providing a feedback forthe angle to the user.

The sensing unit 202 of the apparatus 100 according to an embodiment ofthe present disclosure receives a golf swing motion (three-dimensionaldirection information) of the user and sends a direction vector or acoordinate system (hereinafter, referred to as direction information) tothe data storing unit 204 in a three-dimensional space for themeasurement of an angle between the shoulder and the pelvis and themeasurement of a relative angle change of a golf club based on anaddress point.

The sensing unit 202 of the X-factor feedback apparatus 100 according toan embodiment of the present disclosure may collect data for measuringthe change of angle, which represents an X-factor in a golf swing of theuser, namely the degree of twist of the shoulder and the pelvisaccording to the progress of swing, through sensors. In order to measurethe direction information in the three-dimensional space for themeasurement of the angle, various kinds of sensors may be used. Forexample, a vision sensor may be used to detect a location of animportant joint portion (for example, the shoulder and the pelvis) ofthe user in the three-dimensional space so that a relatively twistdegree between the shoulder and the pelvis is calculated to deduce thechange of X-factor. In another case, an IMU sensor may be attached tothe shoulder, the pelvis or the like to calculate the change of X-factorby using turning information obtained from the IMU sensor according tothe progress of swing. In addition, a hybrid method using both thevision sensor and the IMU sensor may also be used. If both the visionsensor and the IMU sensor are used, the direction information may bemeasured by homogenizing a coordinate system by means of calibration,measuring direction information of the shoulder (or, the pelvis and thegolf club) through a vision sensor and attaching the IMU sensor to thepelvis (or, the shoulder and the golf club).

In the sensing unit of the apparatus according to an embodiment of thepresent disclosure, the sensor for sensing a golf swing motion may useeither a contact-type sensor or a non-contact type sensor. In detail, inthe contact type, in a state where a sensor is attached to or contacts ahuman body, location, rotation or movement information of the contactingsensor is received to tract a motion. Representatively, systems using anoptical motion tracker (which attaches a marker to a human body to betraced and traces a motion of the marker in a three-dimensional spaceaccording to the body motion), an acceleration sensor (which is attachedto a human body and outputs an acceleration value of the attachmentportion according to a motion to estimate a motion of the body), apressure sensor (which measures an input pressure, and for example, in acase where pressure sensors are installed at the bottoms of both feet,the pressure sensors may measure the change of ground reaction forceaccording to time), an IMU sensor (which outputs the degree of turn of abody portion to which the sensor is attached) or the like may be used.In the non-contact type, in a state where a sensor or other substance isnot attached or adhered to a human body, a body motion is traced byusing a camera (or, a vision sensor). Since a user does not feel senseof difference, the user may perform a free swing.

According to an embodiment of the present disclosure, the data storingunit 204 successively receives three-dimensional direction informationof each of the shoulder, the pelvis and the golf club in the golf swingof the user input from the sensing unit, collects the information tillthe swing terminates, and transmits the information to the analyzingunit 206. The swing termination point where data collection ends may bedefined in various ways, such as by an input of a user or as a pointwhere the collected three-dimensional direction information has notchanged for a certain period. In addition, since the collectedthree-dimensional direction information is obtained to be accuratelysynchronized on a time axis, the direction information of the shoulder,the pelvis and the golf club obtained at a certain time may be stored inpairs.

FIG. 3 a shows the analyzing unit 206 of the X-factor feedback apparatusaccording to an embodiment of the present disclosure. The analyzing unit206 may include a calculating unit 302 and a point extracting unit 304.The sequential three- dimensional direction information of shoulder andthe pelvis may be input to the analyzing unit 206, and the analyzingunit 206 may output an analysis result of the three-dimensionaldirection information. The analysis result may include a calculatedvalue of the angle between the shoulder and the pelvis, the backswingtop point or the like.

According to an embodiment of the present disclosure, the calculatingunit 302 of the analyzing unit 206 of the X-factor feedback apparatusmay calculate the change of angle between the shoulder and the pelvisbased on the three-dimensional direction information stored in the datastoring unit 204 and may calculate a relative angle change of the golfclub in the swing motion based on the location of the golf club at anaddress posture. The address posture may be defined as a direction inwhich the club head is directed perpendicular to the ground.

The twist angle of the shoulder and the pelvis mentioned in thespecification represents an interior angle between a line (vector)connecting both the shoulders in the three-dimensional space and a line(vector) connecting both the pelvises (see FIG. 6). Generally, theX-factor in the golf swing represents the degree of twist between theshoulder and the pelvis at the backswing top point, which may bemeasured through the interior angle between two vectors, and theinterior angle between vectors may be calculated by using the vectorinner product in Equation 1.

The calculating unit 302 of the X-factor feedback apparatus according toan embodiment of the present disclosure may calculate angle between theshoulder and the pelvis by calculating an angle in the directioninformation of the shoulder and the pelvis in the three-dimensionalspace, obtained by the sensing unit 202 and input from and synchronizedby the data storing unit 204. For example, in a case where athree-dimensional direction vector (x_(arm)) of the shoulder and adirection vector (x_(club)) of the golf club are obtained, a relativeangle θ of the shoulder and the pelvis in the three-dimensional spacemay be calculated by Equation 1 below.

x _(upper) x _(heap) =∥x _(upper) ∥∥x _(heap)∥cos(θ),0≦θ≦π  Equation 1

Here, x_(upper) represents a three-dimensional direction vector of theshoulder, and x_(heaf) represents a three-dimensional direction vectorthe pelvis.

According to an embodiment of the present disclosure, a turning datagroup of each of the upper body and the pelvis in the three-dimensionalspace, which is collected from the IMU sensor attached to the upper bodyand the pelvis of the user in the golf swing of the user, is received byinput, and the degree of relative twist or turn of the upper body andthe pelvis may be calculated from the turning data of each of the upperbody and the pelvis.

The point extracting unit 304 which may be included in the analyzingunit of the X-factor feedback apparatus according to an embodiment ofthe present disclosure may extract important points of the golf swingaccording to a relative turning angle based on an address point. Theimportant swing points may include a backswing top point and an impactpoint in order to evaluate an X-factor.

The degree of twist of the shoulder (the upper body) and the pelvis maybe regarded as a desirable golf swing when a relative twist of the upperbody and the pelvis in the three-dimensional space or a distortion ofthe upper body corresponds to the range of 50° to 53° at a backswing topposture. In other words, the X-factor should be in a suitable level of50° to 53°. Therefore, it is important to check the backswing top point.

In order to check important points, important points corresponding toimportant motions in the golf swing may be extracted according to arelative turning angle of the golf club based on the location of thegolf club at the address point, by using the sensor described above.

FIG. 3 b is a graph showing a relative turning angle of a golf club inthe progress of swing based on the golf club at the address point. Inview of the relative turning angle of a golf club expressed on a timeaxis, the turning angle of the golf club has a maximum value at thebackswing top point. Since the value does not change greatly for acertain time, the angular speed is close to 0. In addition, at theinstant of an impact, the turning angle of the golf club decreases andthen increases, and the angular speed changes from a negative value to apositive value. Therefore, a zero-crossing point of the angular speedmay be defined as the impact point. In another case, the backswing toppoint may be defined based on a turning angle of the golf club, and theimpact point may be defined as an instant where a ball starts movingwhen being actually hit, which may be sensed by using a sensor.

According to an embodiment of the present disclosure, the determiningunit 208 of the X-factor feedback apparatus 100 determines the degree oftwist (angle) of the shoulder and the pelvis of a user at the backswingtop point. The X-factor may be evaluated as being more desirable whenbeing closer to the range of 50° to 53° mentioned above. In detail, inEquation 1, θ represents an angle which is a relative twist of the upperbody and the pelvis in the three-dimensional space, and thethree-dimensional data of the upper body and the pelvis obtained at thebackswing top point in the golf swing obtained by the point extractingunit may be applied to Equation 1 to determine the degree of twist ofthe shoulder and the pelvis in the swing of the user.

The determining unit 208 of the X-factor feedback apparatus 100according to an embodiment of the present disclosure may generate agraded feedback comment and a score for improving the X-factor in thegolf swing of the user by using the three-dimensional directioninformation of the shoulder and the pelvis and the backswing top pointinformation, transmitted from the analyzing unit 206, and suchinformation may also be generated by another device included in theoutput unit. The generated feedback comment and score may be generatedin advance according to the range of angle between the shoulder and thepelvis based on the information collected from a golf swing specialistgroup and stored in the apparatus.

FIG. 4 shows a relation table about a feedback comment and a scoreaccording to the range of angle between the shoulder and the pelvis ofthe user at the backswing top point. In other words, the determiningunit 208 of the X-factor feedback apparatus 100 according to anembodiment of the present disclosure may generate the feedback commentand the score based on the relation table of FIG. 4.

In an embodiment of the present disclosure, the X-factor feedbackapparatus may include the output unit 210 for providing feedbackinformation about the X-factor to the user. The feedback information maybe a feedback or a score, without being limited thereto. The output unit210 may receive the X-factor (the angle between the shoulder and thepelvis at the backswing top point) about the angle between the shoulderand the pelvis and output a graded feedback comment, a score or thelike. The graded feedback comment and the score may be stored in thedata storing unit 204 in advance, and a result corresponding to theangle between the shoulder and the pelvis of the user at the backswingtop point may be output. The feedback comment and the range anglebetween the shoulder and the pelvis may be prepared based on the dataprovided from a specialist group.

The output unit 210 of the X-factor feedback apparatus according to anembodiment of the present disclosure may provide a feedback to the userby using audio/video multimedia data. In other words, a user mayrecognize the feedback information through a display device or a sounddevice (a speaker) having a graphic-based interface or a voice-basedinterface. In addition, according to an embodiment of the presentdisclosure, the feedback information may be provided to the user basedon the table relating to the X-factor previously stored in the datastoring unit

An X-factor feedback method according to an embodiment of the presentdisclosure may include sensing three-dimensional direction informationof the shoulder, the pelvis and a golf club in a golf swing motion of auser (S501), collecting, synchronizing and storing the sensedthree-dimensional direction information (S502), calculating the changeof angle in the three-dimensional direction information of the shoulderand the pelvis based on the stored data information (S503), extracting abackswing top point in the swing motion (S504), determining an anglebetween the shoulder and the pelvis at the backswing top point (S505),and outputting (providing) feedback information to the user based on thedetermined angle (S506).

In the X-factor feedback method according to an embodiment of thepresent disclosure, the degree of twist of the shoulder and the pelvis,namely an angle, may be calculated by using Equation 1 above.

In the X-factor feedback method according to an embodiment of thepresent disclosure, an angular speed for a turning angle of the golfclub of the user may be calculated after the address point in order toextract the backswing top point. In addition, a point where the angularspeed is 0 may be defined as the backswing top point, or a point wherethe angle has a maximum value may be defined as the backswing top point.In this case, in Operation of sensing a swing motion, it may be requiredto sense three-dimensional direction information of the arm and the golfclub in addition to the shoulder and the pelvis of the user. Inaddition, the angular speed for a turning angle of the golf club of theuser may be calculated by using a marker or marker-less user motionrecognition method or by using the sensors mentioned above.

In the X-factor feedback method according to an embodiment of thepresent disclosure, the feedback information provided to the user may beprovided based on the relation table relating to the feedback commentand the score according to the angle between the shoulder and thepelvis, stored in advance, and the relation table may be configured sothat the angle between the shoulder and the pelvis is divided into aplurality of sections in the range of 43° to 53°.

The above methods may be implemented with various computer-executableprograms and recorded on computer-readable media. The computer-readablemedia may include program commands, data files, data structures or thelike, solely or in combination.

Even though the present disclosure has been described with reference tothe embodiments depicted in the drawings, it is just an example, and aperson skilled in the art will understand that various changes ormodifications can be made therefrom. However, such modifications shouldbe regarded as belonging to the scope of the present disclosure.Therefore, the sincere scope of the present disclosure should be definedby the appended claims.

What is claimed is:
 1. An X-factor feedback apparatus, comprising: asensing unit for sensing three-dimensional direction information of theshoulder, the pelvis and a golf club in a golf swing motion of a user;an analyzing unit for calculating the change of an angle in thethree-dimensional direction information and extracting a backswing toppoint from the swing motion; a determining unit for determining an anglein the three-dimensional direction information of the shoulder and thepelvis at the backswing top point; and an output unit for providingfeedback information to a user based on the determined angle.
 2. TheX-factor feedback apparatus according to claim 1, wherein the analyzingunit includes: a calculating unit for calculating a relative anglechange of the golf club based on the change of an angle in thethree-dimensional direction information and an address posture; and apoint extracting unit for extracting the backswing top point based onthe calculated change of angle.
 3. The X-factor feedback apparatusaccording to claim 1, wherein the sensing unit includes an IMU sensor ora vision sensor.
 4. The X-factor feedback apparatus according to claim1, wherein the output unit provides the feedback information to the userbased on a relation table relating to a feedback comment and a scoreaccording to an angle between the shoulder and the pelvis, previouslystored.
 5. The X-factor feedback apparatus according to claim 1, furthercomprising a data storing unit for collecting, synchronizing and storingthe sensed three-dimensional direction information, wherein theanalyzing unit calculates the angle in three-dimensional directioninformation of the shoulder and the pelvis based on the stored datainformation.
 6. The X-factor feedback apparatus according to claim 1,wherein the output unit provides the feedback information to the user byusing a display device or sound device having a graphic-based interfaceor a voice-based interface.
 7. An X-factor feedback method, comprising:sensing three-dimensional direction information of the shoulder, thepelvis and a golf club in a golf swing motion of a user; calculating thechange of an angle in the three-dimensional direction information of theshoulder and the pelvis; extracting a backswing top point in the swingmotion; determining an angle in the three-dimensional directioninformation of the shoulder and the pelvis at the backswing top point;and providing feedback information to the user based on the determinedangle.
 8. The X-factor feedback method according to claim 7, whereinsaid calculating of the change of an angle in the three-dimensionaldirection information of the shoulder and the pelvis includescalculating a relative angle change of the golf club based on an addressposture, wherein said extracting of a backswing top point in the swingmotion includes extracting the backswing top point based on the changeof a calculated angle of the golf club.
 9. The X-factor feedback methodaccording to claim 7, wherein said calculating of the change of an anglein the three-dimensional direction information of the shoulder and thepelvis uses an equation defined below:x _(upper) ·x _(heap) =∥x _(upper) ∥∥x _(heap)∥cos(θ),0≦θ≦π where θrepresents a relative angle of the shoulder and the pelvis in athree-dimensional space, x_(upper) represents a three-dimensionaldirection vector of the shoulder, and x_(heaf) represents athree-dimensional direction vector of the pelvis.
 10. The X-factorfeedback method according to claim 8, wherein, in said extracting of abackswing top point in the swing motion, a point where an angular speedof the calculated golf club is 0 is defined as the backswing top point.11. The X-factor feedback method according to claim 7, wherein, in saidproviding of feedback information to the user, a feedback comment and ascore are provided to the user based on a relation table relating to afeedback comment and a score according to an angle between the shoulderand the pelvis, previously stored.
 12. The X-factor feedback methodaccording to claim 11, wherein the relation table is configured so thatthe angle between the shoulder and the pelvis is divided into aplurality of sections in the range of 43° to 53°.
 13. The X-factorfeedback method according to claim 7, further comprising: collecting,synchronizing and storing the sensed three-dimensional directioninformation, wherein, in said calculating of the change of an angle inthe three-dimensional direction information of the shoulder and thepelvis, the change of angle is calculated based on the stored datainformation.
 14. The X-factor feedback method according to claim 7,wherein said providing of feedback information to the user includes:providing the feedback information to the user by using a display deviceor a sound device having a graphic-based interface or a voice-basedinterface.